Dry-type transformers, for example, can have power ranges from a few 100 kVA to a few 10 MVA and higher, and can have voltages in the range of from 6 kV up to a few 10 kV. In contrast to oil-type transformers, in which the transformer can be arranged in an oil-filled tank, whereby the insulating clearances can be correspondingly reduced, in the case of a dry-type transformer correspondingly increased complexity for the insulation can be involved.
It is known that insulation layers between different winding layers can be used in the manufacture of transformer windings, for example, for dry-type transformers, in order to increase the voltage loading capacity of such a winding. The insulation layers can be produced from a wound insulation strip, for example a resin-impregnated fiber or glass fiber roving. This can be applied by means of the same winding device which can also be used for winding the electrical conductor on a coil former. Depending on the specifications placed on the insulation layer to be manufactured, a winding operation of conductor and insulation strip can be performed sequentially or synchronously.
The insulation strip can be provided in small widths, for example 5 mm, on corresponding rollers, wherein in each case a plurality of, for example 12, 16 or 24, such strips can be wound in parallel, with the result that, in the mentioned example, an effective winding width of 6 cm, 8 cm or 12 cm would result. The use of such narrow strips instead of a single insulation strip with a greater width can be used because the insulation strips can be moved back and forth along the winding axis in an oscillatory movement during the winding operation. For example, at the turning points in the movement, an excessively wide width of the insulation strip can result in the formation of folds, for example, as a result of which the insulation capacity of the wound insulation layer can be negatively influenced.
In order to enable guidance of the individual insulation strips in a manner which is relatively parallel with respect to the winding device and therefore as relatively seamless an application as a homogeneous winding layer, the individual strips can be guided by a guide device, for example, a so-called winding comb. This can have prongs which are relatively thin, by means of which the respective insulation strips can be guided. Since the insulation strips running next to one another can be intended to form a homogenous and seamless layer, for reasons of insulation, however, the insulation strips can be bent on passage through the winding comb owing to the width of the respective prongs.
The bending can be predominantly maintained during the advancing movement of the insulation strip from the winding comb up to the surface, with the result that adjacent insulation strips cannot abut one another in impact-free fashion. As a result, the insulation capacity of the wound insulation layer can be negatively influenced, which can be compensated for by a correspondingly greater layer thickness.
The disclosure discloses a device for winding a transformer winding, which can include a transformer winding with a wound intermediate insulation layer which is relatively homogenous.